On Sun, Jul 23, 2000 at 08:35:16PM +0400, Khimenko Victor wrote:
> > Fortunately all UDMA transfers are protected by safe enough CRC to see
> > if a transfer fails. This way you can know your cable won't do UDMA/66
> > and switch to something slower. (UDMA/44 seems to work on most 40-wire
> > cables just fine). If that doesn't work, go even lower. Something like
> > modem autobauding ...
>
> If it'll work like modem autobauding here (connect with speed limit=14400
> and get 1.5Kbytes/second, connect with 33600 and spend 95% of time for
> retrains and thus transfer with 0.1Kbytes/second speed in the end) then
> better not...
>
> P.S. Sorry, could not resist...
:)))))))) It'd be like this if you let UDMA/66 enabled on a 40-wire
cable. What I meant is that after a *single* CRC error the speed would be
lowered to the next lower step (UDMA 100, 66, 44, 33, 16) and if even
UDMA/16 doesn't work, then fall back to PIO.
PS. You have damn bad modems if they behave like that. Mine just lower
the rate until the rate of retrains is acceptable. But yes, I have to
admit that Morotola 3265's tend to be expensive, yes.
-- Vojtech Pavlik SuSE Labs- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Sun Jul 23 2000 - 21:00:20 EST